A few things you should probably consider:
Even if the CPU is the correct socket, FSB, voltage, etc. and is electrically compatible, it's not guaranteed to work. The BIOS in most laptops is coded to accept a limited number of different CPUs. If the CPU you insert isn't one of those, it will either work only at the lowest clock speed, or not work at all. Physically getting to the CPU isn't easy, either, and if you haven't successfully disassembled and reassembled a laptop before, you may want to reconsider. Plus, like cee_64 mentioned, your warranty will be void once you open the laptop.
CPU is only one part of 'performance'. If you want it to be faster while multitasking several large programs, you may be better off upgrading the RAM. If you want programs to load faster, upgrade to a faster hard drive. For gaming, a better graphics processor is best, but is not an option on the vast majority of laptops. If web pages and downloads take too long, upgrade your Internet connection. If you're running Windows Vista or later, with less than 2GB of RAM, you'll probably see the best improvement by upgrading to at least 3GB.
If you computer was fast when you bought it, has been slowing down since then, and is now performly really slowly, you should look at the software level. Try disabling programs from starting when you boot your computer (using msconfig). You may also have a virus/spyware on the computer (even if your antivirus doesn't warn you, and even if you don't notice anything unusual, like pop-ups). Try doing a free online scan from Panda Security (ActiveScan) and/or Trend Micro (HouseCall). Your hard drive may even need to be defragmented.
Feedback
